The government has just finished cleaning up a three-kilometre stretch of Christchurch's Avon River but many say the job is only half done.
Work on the Avon river. Photo: RNZ / Phillippa Tolley
Where the river passes through the CBD, there is already been a noticeable increase in the number of birds and fish, thanks to the removal of silt and the narrowing of the river to increase its flow rate.
The river is one of Christchurch's most recognisable landmarks but for a long time has been filled with rubbish and has been too dirty to consider catching whitebait or fish from.
Rob Kerr, who has been hired by the government to transform it as part of the 100-million-dollar Avon River precinct, said they were already starting to see results.
"We created over a kilometre of new homes in terms of rock formations for the fish and for the eels and so on.
"So I'm getting reports of seeing more and more of those fish and the ducks and all sorts of things. It's going to grow over time, but we're expecting to see a lot of spawning this season, which is kind of exciting."
At this stage the remediation of the river stops as it enters the suburbs and makes its way out to sea, an area still largely made up of abandoned red zoned properties.
The Avon-Otakaro Network wants to see this area turned into a reserve.
Its spokesperson, Evan Smith, said the same amount of money spent on the city section of the river needed to be spent again on the remaining 10 kilometre stretch to the sea.
"There's no point n having a fancy shop window if what lies behind it isn't also clean. There is some value to doing it in the CBD where international visitors see it but to do the job properly, it needs to be catchment wide."
Mr Smith said plantings to provide areas for the whitebait and fish to spawn under and wetlands to filter stormwater before it enters the river would all help the lower reaches of the river.
He said improving the river beyond the CBD wasn't just a 'nice to have', and that one study showed it would return $1 billion worth of benefits over ten years.
"That's in terms of savings on health budgets, because people have access to an environment that allows them passive and active recreation but also those eco system services.
"The ability to act as the kidneys for the storm water system means they don't have to be treated further down the path by mechanical means."
Fisherman Dale Erridge hasn't fished for whitebait ever since the earthquakes led to sewage overflows being pumped directly into the river.
He still fishes for trout however and would like to see it cleaned up.
"A lot of the rubbish that gets chucked in the river should be taken out for starters. The weed is getting a bit of a problem for the fish as well so it needs removing as well."
Joseph Hullen from the Ngai Tuahuriri hapu sits on an advisory group that has input into government anchor projects such as the Avon River upgrade.
Speaking in a private capacity at a recent information day on the river clean up, he told me that, for Maori, completing the clean-up right to the river mouth is important.
"We have a saying, Ki Uta Ki Tai, From the Mountains to the Sea, so if there's a corridor of connectivity all the way through, that would be our end goal.
"The ability to do something quintessentially New Zealand as go fishing for whitebait, to be able to swim in the river, is something we'd desire for everybody."
The government has yet to make a decision on what will happen to the stretch of the Avon River that passes through the red zone but is expected to begin consulting on this later in the year.